Epitope mapping of antibodies against TDP-43 and detection of protease-resistant fragments of pathological TDP-43 in amyotrophic lateral sclerosis and frontotemporal lobar degeneration

• Published in: Biochemical and biophysical research communications 2012-01, Vol.417 (1), p.116-121
• Main Authors: Tsuji, Hiroshi, Nonaka, Takashi, Yamashita, Makiko, Masuda-Suzukake, Masami, Kametani, Fuyuki, Akiyama, Haruhiko, Mann, David M.A., Tamaoka, Akira, Hasegawa, Masato
• Format: Article
• Language: English
• Subjects: Aggregation; Alpha-synuclein; ALS; Amino Acid Sequence; Amino acids; Amyotrophic lateral sclerosis; Amyotrophic Lateral Sclerosis - metabolism; Animal models; Animals; Antibodies - chemistry; Antibodies - immunology; Antibodies, Monoclonal - chemistry; Antibodies, Monoclonal - immunology; Brain; Brain - immunology; Brain - metabolism; Brain Chemistry; DNA-binding protein; DNA-Binding Proteins - chemistry; DNA-Binding Proteins - immunology; DNA-Binding Proteins - metabolism; Epitope Mapping; Frontotemporal dementia; Frontotemporal Lobar Degeneration - metabolism; FTLD; Humans; Mice; Molecular Sequence Data; Monoclonal antibodies; Peptide Hydrolases - chemistry; Proteinase; Tau
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1016/j.bbrc.2011.11.066

► We mapped the epitopes of anti-TDP-43 antibodies. ► The monoclonal labeled human TDP-43 by recognizing Glu204, Asp205 and Arg208. ► The antibodies reacted with pathological C-terminal fragments of 24 and 26kDa. ► The epitope is protease-resistant in the abnormal TDP-43. ► The antibodies and methods are useful for the characterization of abnormal TDP-43. TAR DNA-binding protein of 43kDa (TDP-43) is the major component of the intracellular inclusions in amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). Here, we show that both monoclonal (60019-2-Ig) and polyclonal (10782-2-AP) anti-TDP-43 antibodies recognize amino acids 203–209 of human TDP-43. The monoclonal antibody labeled human TDP-43 by recognizing Glu204, Asp205 and Arg208, but failed to react with mouse TDP-43. The antibodies stained the abnormally phosphorylated C-terminal fragments of 24–26kDa in addition to normal TDP-43 in ALS and FTLD brains. Immunoblot analysis after protease treatment demonstrated that the epitope of the antibodies (residues 203–209) constitutes part of the protease-resistant domain of TDP-43 aggregates which determine a common characteristic of the pathological TDP-43 in both ALS and FTLD-TDP. The antibodies and methods used in this study will be useful for the characterization of abnormal TDP-43 in human materials, as well as in vitro and animal models for TDP-43 proteinopathies.